Which of these describes a way the body maintains homeostasis in a cold environment? a cramping b perspiring c relaxing d shivering

The distribution of related animals and plants across the world

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What does polymerase chain reaction (pcr) do? o a. separates dna fragments by size o b. cuts a dna sample into fragments o c. provides an overall picture of a person's chromosomes o d. makes more copies of a sample of dna